Tel Aviv University


Tel Aviv University
Supplementary Condensed Matter Theory Seminar

Academic Year  2004 - 2005


The seminar is held in Room 222 in the Shenkar Physics Building, on Thursdays at 13:00.  

 

January 6, 2005

Student Thesis Seminar

"Does dephasing time saturate at low temperatures?"

Moshe Eshkol
Dept. of Condensed Matter Physics, Tel Aviv University


     The observation of quantum transport phenomena in metals and semiconductors is limited by the eventual loss of phase coherence of the conducting electrons on the time scale τφ (dephasing time). We addressed the question whether τφ saturates at low temperatures. We used weak localization (WL) studies to measure τφ in a two-dimensional electron gas (2DEG), in GaAs/AlGaAs heterostructures at low temperatures. We used a novel temperature calibration method based on the Integer Quantum Hall Effect, in order to ascertain the temperature of the 2DEG when there is a lack of good thermal contact with the bath. We claim that the apparent saturation is an outcome of electron heating due to electromagnetic radiation or some other extrinsic source, and that therefore, it does not represent any dephasing-time saturation as such.

Thesis Adviser: Prof. Alexander Palevsky, x8193
 
Fall 2004 Schedule Spring 2005 Schedule

For more information or for directions to 222 Shenkar please contact: Chava Balson  03-6408300

To suggest potential speakers or register feedback contact:  Ron Lifshitz  03-6405145


Sponsored by:   The Condensed Matter Physics Department, The School of Physics & Astronomy, Tel Aviv University.